In automotive electronics, an electronic control unit refers to an embedded system that controls one or more electrical systems and/or electrical subsystems of a vehicle. The number of electronic control units utilized may vary depending on the vehicle controls and/or options, with some vehicles having one hundred (or more) electronic control units.
The electronic control units used to control the operation of appliances associated with the vehicle are connected in a network configuration, such as through a common bus. This distributed communication system may be mounted in the vehicle and data and other messages may be communicated between the electronic control units.
These distributed communication systems are based on the concept that distributing features between discrete electronic control units reduces overall system complexity by having several electronic control units with a focused group of features. In the automotive environment, these systems may vary with grade and the variations may be handled by adding features to these discrete electronic control units. Traditionally, handling the variations means each discrete electronic control unit must vary with the whole system in order to be aware of the feature differences with each system variation, but this defeats the purpose of distributing the features.